Please help bbg's

Joan writes four numbers on the board in standard form, and then she writes their scientific notation

Pastoral farming is best described as a. a method of raising livestock and moving herds b. an african method of agriculture c. a method of cultivating crops on poor soils d. a common method of desert farming select the best answer from the choices provided a b c d

If you burn 46.6 g of hydrogen and produce 416 g of water, how much oxygen reacted